Tranexamic acid oral solution

ABSTRACT

Methods and compositions are provided for treating a patient having a bleeding disorder during or after a dental procedure to reduce bleeding or need for factor replacement therapy. Aqueous pharmaceutical compositions are provided comprising tranexamic acid, sodium carboxymethyl cellulose, Tween® 20, and menthol wherein the composition exhibits good long term stability, little to no discoloration over time, and reduced bitterness compared to a control solution of tranexamic acid and water.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. patent application Ser. No.16/243,234, filed Jan. 9, 2019, which claims the benefit of U.S.Provisional Patent Application No. 62/619,634, filed on Jan. 19, 2018,the disclosure of which are incorporated by reference in their entiretyherein.

BACKGROUND

Tranexamic acid is an antifibrinolytic agent that competitively inhibitsthe activation of plasminogen to plasmin, an enzyme that degrades fibrinclots, fibrinogen, and other plasma proteins, including thepro-coagulant factors V and VIII.

Tranexamic acid has a long history of clinical use as ananti-fibrinolytic drug. Approved uses include a range of indications:short-term use for prevention or treatment of hemorrhage underconditions of general or local fibrinolysis, which includes for instancepre-/post-operative hemorrhage, heavy menstrual bleeding and hereditaryangioneurotic edema.

Commercial compositions including CYKLOKAPRON (tranexamic acid)injection and oral tablets were approved for use in the United States in1986. CYKLOKAPRON injection is used for dental extraction in patientswith hemophilia. CYKLOKAPRON tablets are used to prevent excess bleedingin patients with menorrhagia (heavy menstrual bleeding). More recently,LYSTEDA (Tranexamic Acid) tablets were approved for use in the treatmentof heavy menstrual bleeding. However, in order to limit systemicexposure to tranexamic acid, alternative topical formulations aredesirable.

Tranexamic acid oral rinse compositions are known. Prior artcompositions are not stable for long term shelf storage and are subjectto discoloration. Additionally, bitterness of prior art oral rinsesolutions of tranexamic acid has limited their use.

U.S. Pat. No. 4,465,662, Sato et al., discloses oral compositionscomprising tranexamic acid and carvone that exhibit reduced bitterness.Toothpaste formulations comprising specific ratios of sorbitol toglycerol are disclosed for prevention of discoloration. However, asprovided herein, it has been discovered that solution formulationscontaining tranexamic acid and sorbitol and/or glycerin exhibitdiscoloration upon storage.

EP 2695605 discloses liquid compositions comprising tranexamic acid in(tris(hydroxymethyl)aminomethane) (TRIS) or glycine buffer systems asexhibiting decreased discoloration compared to phosphate or isoleucinebuffer systems in accelerated stability tests.TRIS or glycine bufferingagents were said to maintain pH 6 to 8 to avoid discoloration. However,TRIS or glycine buffers may not be optimal for a target pH range ofabout pH 5 to 6 for use in formulation development.

Clinical studies have demonstrated that the use of local tranexamicacid, as a supplement to the currently used systemic therapy,significantly reduces the incidence of bleeding during or after dentalprocedures. For example, A. H. P. Lee et al. in 2005, British Dentaljournal, Vol. 198: pp. 33-38, showed effectiveness in controllinghemorrhage after dental scaling in people with haemophilia by usingtranexamic acid mouthwash. Sivakumar Nuvvula et al., 2014, Contemp ClinDent, Vol. 5(1): 49-53, demonstrated use of tranexamic acid mouthwash asan alternative for factor replacement in gingival bleeding during dentalscaling in cases of hemophilia.

Therefore, further improved tranexamic acid oral rinse compositionsexhibiting improved stability and taste characteristics are desirable.

SUMMARY

Some embodiments of the invention provide an aqueous pharmaceuticalcomposition for topical administration of tranexamic acid in the oralcavity. With respect to these embodiments, the composition includeswater, a non-ionic surfactant, a preservative, a viscosity enhancer, athickening agent, a pH adjuster, a sweetener, and a flavoring agent. Thecomposition preferably includes greater than 40% water.

Other embodiments of the invention are directed to an aqueouspharmaceutical composition that includes about 3% wt/vol to about 7%wt/vol tranexamic acid, greater than 40% water, a surfactant, athickening agent, a viscosity enhancer, and a flavoring agent. Withrespect to these embodiments, the composition retains at least about 90%of the tranexamic acid in solution in undegraded form after storage forat least 6 months at about 25° C. and about 40% relative humidity.

In other embodiments, the invention provides a method for reducing orpreventing hemorrhage in a patient having a bleeding disorder during orfollowing a dental procedure. The method includes administering anaqueous pharmaceutical composition comprising tranexamic acid, water, anon-ionic surfactant, a preservative, a viscosity enhancer, a thickeningagent, a pH adjuster, a sweetener, and a flavoring agent.

Still other embodiments are directed to a method for reducing orpreventing hemorrhage in a patient on anticoagulant, fibrinolytic orthrombolytic therapy during or following a dental procedure. The methodincludes administering an aqueous pharmaceutical composition comprisingtranexamic acid, water, a non-ionic surfactant, a preservative, aviscosity enhancer, a thickening agent, a pH adjuster, a sweetener, anda flavoring agent.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 shows chemical structures of tranexamic acid and degradanttranexamic acid related compounds A, B, C and D.

DETAILED DESCRIPTION Definitions

The singular forms “a”, “an” and “the” are intended to include theplural forms as well, unless the context clearly indicates otherwise.

The term “and/or” refers to and encompasses any and all possiblecombinations of one or more of the associated listed items.

The term “about,” as used herein when referring to a measurable valuesuch as an amount of a compound, dose, time, temperature, and the like,is meant to encompass variations within the error of measurement for thespecified amount.

Unless otherwise specified, all percentage “%” values are expressed asweight percent compared to total weight of the composition.

The term “therapeutically effective amount” refers to the amount of acompound that, when administered to a subject for treating a disease orcondition, is sufficient to effect such treatment to fully orsubstantially alleviate the symptoms of the disease state or condition.The “therapeutically effective amount” can vary depending on thecompound, the disease and its severity, and the condition, age, weight,gender etc. of the subject to be treated. In some embodiments, theeffective amount of tranexamic acid is the amount sufficient to preventor alleviate hemorrhage during and following dental procedures. In someembodiments, the effective amount of tranexamic acid is an amountsufficient to avoid reducing, interrupting or discontinuinganticoagulant, fibrinolytic or thrombolytic therapy in a patient in needthereof during and following dental procedures. In some embodiments, theeffective amount of tranexamic acid is an amount sufficient to reducethe need for factor replacement therapy in the patient during andfollowing dental procedures. In some embodiments, the effective amountof tranexamic acid is an amount sufficient to reduce the need forantifibrinolytic therapy in the patient during and following dentalprocedures.

The terms “treating” and “treatment” of a disease state or conditioninclude: (i) preventing the disease state or condition, i.e., causingthe clinical symptoms of the disease state or condition not to developin a subject that may be exposed to or predisposed to the disease stateor condition, but does not yet experience or display symptoms of thedisease state or condition, (ii) inhibiting the disease state orcondition, i.e., arresting the development of the disease state orcondition or its clinical symptoms, or (iii) relieving the disease stateor condition, i.e., causing temporary or permanent regression of thedisease state or condition or its clinical symptoms. In someembodiments, the terms “treating” or “treatment” refer to prevention oralleviation of hemorrhage during and following dental procedures.

The term “solution” refers to a clear, homogeneous liquid dosage formthat contains at least one active pharmaceutical chemical substancedissolved in a solvent or mixture of mutually miscible solvents.

The term “topical administration in the oral cavity” refers toadministration to the skin or mucosa of the mouth. For example, thiswould include a swish and spit administration of a tranexamic acid mouthrinse solution. Administration to the oral mucosa may be performed byswishing the tranexamic acid solution inside the mouth of the patientfor a period of time then spitting it out. In some embodiments, thetranexamic acid oral rinse solution is swished or held in the mouth ofthe patient for at least 30 seconds, at least 45 seconds, at least 60seconds, at least 75 seconds, at least 90 seconds, or at least 120seconds before spitting it out. In some aspects, topical administrationin the oral cavity includes periodontal administration. The tranexamicacid oral rinse composition as provided herein may be administeredtopically in the oral cavity in the form of a solution. For example, thetranexamic acid oral rinse composition may be administered immediatelyafter a dental procedure in patients with hemophilia, comprisingadministering 10 ml of a 5% solution as an oral rinse for two minutes.The administration of the oral rinse may be continued three or fourtimes daily for up to eight (8) days.

Tranexamic Acid

Tranexamic acid, also known as trans-4-(aminomethyl)cyclohexanecarboxylic acid, also referred to as TXA, for example havingCAS RN: 1197-18-8, is an active pharmaceutical ingredient (API) that isa competitive inhibitor of plasminogen activation

Tranexamic Acid

Tranexamic acid is an antifibrinolytic hemostatic agent used to preventor treat severe hemorrhage. Available literature demonstrates theeffectiveness of local antifibrinolytic therapy for patients withinherited bleeding disorders for dental procedures.

Tranexamic acid may be administered intravenously, orally and as a mouthrinse. Historically, tranexamic acid concentrations up to 10 mg per mLblood have no influence on the platelet count, the coagulation time, orvarious coagulation factors in whole blood or citrated blood from normalsubjects. On the other hand, tranexamic acid in concentrations of 1 mgto 10 mg per mL blood prolongs the thrombin time. After intravenous doseof 1 g, the plasma concentration time curve shows a tri-exponentialdecay with a half-life of about 2 hours for the terminal eliminationphase. The initial volume of distribution is about 9 to 12 liters. Theplasma protein binding of tranexamic acid is about 3% at therapeuticplasma levels and seems to be fully accounted for by its binding toplasminogen (does not bind serum albumin). Only a small fraction of thedrug is metabolized (less than 5%). Urinary excretion is the main routeof elimination via glomerular filtration. Overall renal clearance isequal to overall plasma clearance (100 to 116 mL/min), and more than 95%of the dose is excreted in the urine as unchanged drug. Excretion oftranexamic acid is about 90% at 24 hours after intravenousadministration of 10 mg per kg body weight.

Absorption of tranexamic acid after oral administration in humansrepresents approximately 30 to 50% of the ingested dose andbioavailability is not affected by food intake.

Systemically, tranexamic acid binds considerably more strongly thanepsilon aminocaproic acid (EACA) to both the strong and weak sites inthe plasminogen molecule in a ratio corresponding to the difference inpotency between the compounds. The pharmacological significance of thebinding to these different sites has not yet been evaluated. Tranexamicacid does not bind to serum albumin. The plasma protein binding seems tobe fully accounted for by its binding to plasminogen and appears to benegligible at therapeutic plasma levels of 5-10 mg/L.

Possible routes of biotransformation are acetylation or deaminationfollowed by oxidation or reduction. After oral administrationapproximately 50% of the parent compound, 2% of the deaminateddicarboxylic acid, and 0.5% of the acetylated product are excreted.Tranexamic acid is eliminated by glomerular filtration, excretion beingabout 30% at one hour, 55% at three hours and 90% at 24 hours afterintravenous administration of 10 mg per kg body weight. After oraladministration of 10-15 mg per kg body weight, excretion was 1% at onehour, 7% at three hours and 39% at 24 hours.

Intravenous administration of 10 mg per kg body weight gave plasmaconcentrations of 18.3 μg, 9.6 μg and 5 μg per mL one, three and fivehours after the injection. When administered 36-48 hours before surgeryin four doses of 10-20 mg per kg body weight, an antifibrinolyticallyactive concentration (10 μg/mL) of tranexamic acid remained up to 17hours in the tissues investigated, and up to 7-8 hours in the serum.

Tranexamic acid crosses the placenta. After an intravenous injection of10 mg per kg body weight the concentration can rise to about 30 μg permL of fetal serum. Tranexamic acid also passes over into the breast milkduring lactation in concentrations 1/100 of the corresponding serumlevels. After both oral and intravenous administration tranexamic acidpasses into the semen and inhibits its fibrinolytic activity, butwithout affecting the motility of the spermatozoa. The ability oftranexamic acid to cross the blood-brain barrier has been demonstratedwhen administered to patients with ruptured intracranial aneurysms.Tranexamic acid diffuses rapidly to the joint fluid and to the synovialmembrane. In the joint fluid the same concentration was obtained as inthe serum. The biological half-life in the joint fluid was about 3hours.

Three hours after a single oral dose of 25 mg per kg body weight, thepeak serum level was 15.4 mg per L and the aqueous humor level was 1.6mg per L.

Pharmacokinetic studies have compared the distribution of tranexamicacid in plasma and saliva after mouth rinsing and oral administration.After oral administration, the mean plasma concentration of tranexamicacid reached its maximum after 120 minutes at approximatively 7 μg permL, whereas the saliva levels of tranexamic acid were undetectable atany time points. After mouth rinse, the plasma concentrations remainedbelow 2 μg per mL, whereas the concentrations found in saliva wereinitially above 200 μg per mL and remained above therapeutic levels formore than 2 hours. These findings indicate that fibrinolysis in the oralcavity can be inhibited by local administration of tranexamic acid.

An oral rinse dosage form of tranexamic acid for topical administrationwill facilitate the use of antifibrinolytic therapy in dental patientsand minimize systemic exposure from administration of the injectiondosage form.

Excipients

Sodium carboxymethyl cellulose is also known as carboxymethyl cellulosesodium or carboxymethyl cellulose, sodium salt, and acronyms Na CMC, orsodium CMC, for example, having Chemical Abstracts Service RegistryNumber (CAS RN): 9004-32-4, is non-foaming, hydrophilic water solublepolymer that may be used as a thickening agent.

Poloxamer 407 is a non-ionic surfactant also known as Poly(ethyleneglycol)-block-poly(propylene glycol)-block-poly(ethylene glycol), anA-B-A block copolymer having CAS Reg No.: 9003-11-6. Poloxamer 407 hasan HLB (hydrophilic-lipophilic balance) value of 18-23.

Tween 20 is a non-ionic surfactant also known as polysorbate 20, refersto polyoxyethylene sorbitan monolaurate, or polyethylene glycol sorbitanmonolaurate, for example having CAS RN: 9005-64-5, having M.W. 1227.54g/mol.

Tween 80 is a non-ionic surfactant also known as polyoxyethylene(20)sorbitan monooleate, for example having CAS RN: 9005-65-6, havingM.W. 604.816 g/mol.

Sucrose stearate, also known as sucrose monostearate, oralpha-D-Glucopyranoside, beta-D-fructofuranosyl, monooctadecanoate, forexample having CAS RN: 25168-73-4, is a type of non-ionic sucrose estersurfactant.

Sucrose laurate, also known as sucrose monolaurate, orbeta-D-Fructofuranosyl-alpha-D-glucopyranoside, monododecanoate, forexample having CAS RN: 25339-99-5, is a type of non-ionic sucrose estersurfactant.

Compositions

Pharmaceutical compositions in the form of aqueous oral rinseformulations comprising tranexamic acid are described. In someembodiments, an aqueous oral rinse formulation is provided comprisingfrom about 3% wt/vol to about 7% wt/vol, about 4% wt/vol to about 6%wt/vol, or about 5% wt/vol tranexamic acid. In some embodiments, anaqueous oral rinse formulation is provided comprising from about 30 toabout 70 mg/mL, about 40 to about 60 mg/mL, about 45 mg/mL to about 55mg/mL, or about 50 mg/mL tranexamic acid.

In some embodiments, pharmaceutical compositions are provided in theform of aqueous oral rinse formulations comprising tranexamic acid in anamount effective to reduce the need for factor replacement therapy (FRT)in the patient. FRT is a main method for reducing hemorrhage in peoplewith bleeding disorders such as hemophilia A and hemophilia B. However,FRT is expensive, and its use both as plasma and recombinant factortherapy runs the risk of formation of inhibitors. In addition, there isa possibility of transmission of blood borne viruses including HIV,hepatitis A, B, C, G and parvovirus with HRT. In certain aspects theamount effective to reduce the need for factor replacement therapy isabout 10 mL of a 5% oral rinse solution of tranexamic acid, or theequivalent, held in the mouth for 2 minutes. In some embodiments, theeffective amount to reduce the need for factor replacement therapy isabout 5 mL of a 10% oral rinse solution of tranexamic acid, or anequivalent, held in the mouth for about 2 minutes. In some embodiments,an effective amount of tranexamic acid in an oral rinse solution is aconcentration of from about 3% wt/vol to about 12% wt/vol, about 3%wt/vol to about 7% wt/vol, about 4% wt/vol to about 6% wt/vol, or about5% wt/vol tranexamic acid.

In some embodiments, pharmaceutical compositions are provided in theform of aqueous oral rinse formulations comprising tranexamic acid in anamount effective to prevent or reduce hemorrhage in a patient followinga dental procedure such as scaling or tooth extraction. In oneembodiment, a mouth rinse composition having a concentration of about4-6% wt/vol tranexamic acid is employed in an amount of about 10 mL, forexample when used for about 2 minutes, about 4 times daily for 2 to 7days post operatively to reduce the need for intravenousantifibrinolytic therapy. (Hamid et al., 2008).

In some embodiments, aqueous oral rinse tranexamic acid solutionformulations are provided having greater than 40%, greater than 45%, orgreater than 50% by volume water. In some embodiments, any watersuitable for pharmaceutical purposes may be employed. The water isselected from purified water or water for injection as defined by U.S.Pharmacopeia. In a specific embodiment, purified water USP is used.

In some embodiments, an aqueous formulation of tranexamic acid isprovided wherein all components remain in solution, and exhibit littleto no discoloration over storage conditions for at least 3 months, atleast 6 months, at least 9 months, at least 12 months, at least 18months, at least 24 months, at least 30 months, at least 36 months, orat least 48 months under storage at standard room temperature andhumidity conditions, such as 25° C. and 40% relative humidity. In aparticular aspect, stable aqueous tranexamic acid formulations areprovided, exhibiting minimal discoloration as determined by a ΔE* valueof <3, <4, <5, or <7 in a colorimetric assay when stored at 25° C. at40% RH after a period of 3 months, 6 months, 9 months, or 12 months. Inanother particular aspect, stable aqueous tranexamic acid formulationsare provided, exhibiting a ΔE* value of <4, <5, or <7 in a colorimetricassay when stored at 40° C. at 25% RH after a period of 3 months, 6months, 9 months, or 12 months. In some embodiments, the colorimetricassay employs the formula: ΔE*=[ΔL*2+Δa*2+Δb*2]½, using L* a* b*coordinates, as defined herein. In some embodiments, formulations arestored in the dark.

In some embodiments, the tranexamic acid compositions provided hereinmay be stored in glass, HDPE (high density polyethylene), or PET(polyethylene terephthalate) bottles.

In some embodiments, the compositions provided herein capable ofmaintaining at least about 90%, 95%, 97.5%, 98%, 99%, 99.5%, or 99.7% ofthe release, or “as manufactured,” amount of tranexamic acid inundegraded form after storage for at least 6 months at 25° C. at 40%relative humidity when measured by liquid chromatography. In someembodiments, the compositions provided herein capable of maintaining atleast about 90%, 95%, 97.5%, 98%, 99%, or 99.5% of the release, or “asmanufactured,” amount of tranexamic acid in undegraded form afterstorage for at least 12 months at 25° C. at 40% relative humidity whenmeasured by liquid chromatography. In some embodiments, the compositionsprovided herein capable of maintaining at least about 90%, 95%, 97.5%,98%, 99%, 99.5% of the release, or “as manufactured,” amount oftranexamic acid in undegraded form after storage for at least 18 monthsat 25° C. at 40% relative humidity when measured by liquidchromatography. In some embodiments, the compositions provided hereincapable of maintaining at least about 90%, 95%, 97.5%, 98%, 99% of therelease, or “as manufactured,” amount of tranexamic acid in undegradedform after storage for at least 24 months at 25° C. at 40% relativehumidity when measured by liquid chromatography. In some embodiments,the compositions provided herein capable of maintaining at least about90%, 95%, 97.5%, 98%, 99%of the release, or “as manufactured,” amount oftranexamic acid in undegraded form after storage for at least 36 monthsat 25° C. at 40% relative humidity when measured by liquidchromatography. In some embodiments, the compositions provided hereincapable of maintaining at least about 90%, 95%, 97.5%, 98%of therelease, or “as manufactured,” amount of tranexamic acid in undegradedform after storage for at least 48 months at 25° C. at 40% relativehumidity when measured by liquid chromatography.

In some embodiments, the compositions provided herein capable ofmaintaining at least about 90%, 95%, 97.5%, 98%, 99%, 99.5%, or 99.7% ofthe release, or “as manufactured,” amount of tranexamic acid inundegraded form after storage for at least 6 months at 40° C. at 25%relative humidity when measured by liquid chromatography. In someembodiments, the compositions provided herein capable of maintaining atleast about 90%, 95%, 97.5%, 98%, 99%, 99.5%, 99.7%, or 99.8% of therelease, or “as manufactured,” amount of tranexamic acid in undegradedform after storage for at least 12 months at 40° C. at 25% relativehumidity when measured by liquid chromatography. In some embodiments,the compositions provided herein capable of maintaining at least about90%, 95%, 97.5%, 98%, 99%, 99.5%, 99.7%, or 99.8% of the release, or “asmanufactured,” amount of tranexamic acid in undegraded form afterstorage for at least 18 months at 40° C. at 25% relative humidity whenmeasured by liquid chromatography.

In some embodiments, a solution composition comprising tranexamic acid,sodium carboxymethyl cellulose, propylene glycol and menthol exhibitsreduced bitterness, improved overall taste, and/or improved mouth feelcompared to a solution of tranexamic acid alone, and exhibits goodstorage stability without phase separation.

pH Adjuster

Tranexamic acid in aqueous solution without a pH adjuster may range frompH 6.5 to 8.0. Therefore, in some embodiments, a pH adjuster is employedin the tranexamic aqueous formulations to adjust the pH to 4.5 to 6.5,preferably pH 5.0 to 6.0, or about pH 5.5. In some embodiments, the pHadjuster is any pharmaceutically acceptable pH adjuster known in theart. In some embodiments, the pH adjuster is selected from phosphoricacid, hydrochloric acid, nitric acid, sulfuric acid, hydrobromic acid,citric acid, malic acid, adipic acid, ascorbic acid, tartaric acid,lactic acid, and combinations thereof. In some embodiments, the pHadjuster is phosphoric acid. The pH adjuster may be employed in thecomposition in an amount in the range of about 0.1 wt % to 1 wt %, orabout 0.2 to 0.5 wt %, or about 0.3 to 0.4 wt % to adjust the pH rangeas specified.

Surfactant

In some embodiments, an aqueous formulation of tranexamic acid isprovided that is a solution formulation comprising a surfactant. Thesurfactant may serve as an emulsifier or dispersing agent to enhancehomogeneity of the solution composition. In some embodiments, thesurfactant is selected from a non-ionic surfactant that helps avoidphase separation of the composition. In some embodiments the surfactantis selected from any pharmaceutically acceptable non-ionic surfactantknown in the art. In some embodiments, the composition does not includean anionic surfactant.

In some embodiments, the surfactant is a non-ionic surfactant selectedfrom polyoxyethylene sorbitan monolaurate (e.g., Tween® 20),polyoxyethylene (20)sorbitan monooleate (e.g., Tween® 80), Poly(ethyleneglycol)-block-poly(propylene glycol)-block-poly(ethylene glycol) (e.g.,Poloxamer® 407), Sucrose Stearate, and Sucrose Laurate. In a specificembodiment, the surfactant is Tween 20. The surfactant is used in theaqueous tranexamic acid formulation in an amount from 0.1 to 2 wt %, or0.5 to 1 wt % based on the weight of the composition.

Thickening Agent

In some embodiments, an aqueous formulation of tranexamic acid isprovided that is a solution formulation comprising a thickening agentthat is a hydrophilic water soluble polymer. In some embodiments, thethickening agent is a water soluble pharmaceutically acceptable polymer.In some embodiments, the thickening agent is not a superabsorbentpolymer such as sodium polyacrylate. In some embodiments, the thickeningagent may be selected from xanthan gum, sodium alginate, sodiumcarboxymethyl cellulose or starch. In some embodiments, the thickeningagent is a water soluble, non-foaming pharmaceutically acceptablepolymer. Foam testing may be performed by vigorously shaking a 0.1%solution of the thickening agent in water. If the thickening agent isnon-foaming, no layer of foam appears. This test distinguishes, e.g.,sodium carboxymethyl cellulose from other cellulose ethers and alginatesand natural gums. In some embodiments, the thickening agent is sodiumcarboxymethyl cellulose. In some embodiments, the thickening agent ispresent in the aqueous tranexamic acid solution composition at from 0.05wt % to 1 wt %, 0.1 wt % to 0.5 wt %, or 0.2 wt % to 0.3 wt %. Thethickening agent aids in improving mouthfeel of the composition, andhelps to alleviate the bitter taste of the composition when combinedwith the flavoring.

In some embodiments, compositions are provided comprising tranexamicacid, water, a thickening agent and a surfactant, wherein thecompositions exhibit less average bitterness than a control solutionconsisting of tranexamic acid and water. In some embodiments, aqueoustranexamic acid compositions are provided comprising no less than 40%water by volume, a thickener and a surfactant that exhibit less averagebitterness than a control solution consisting of tranexamic acid inwater and score at least 1.0 average points higher, or at least 1.5average points higher on a 5 point bitterness scale wherein 1 is mostbitter and 5 is least bitter. The compositions may also include one ormore of a sweetener, pH adjuster, viscosity enhancer, preservative and aflavoring agent. Average bitterness of a tranexamic acid oral rinse testsolution may be determined in a taste test performed by at least 4 tastetesters and compared to a control solution consisting of tranexamic acidand water, wherein the tranexamic acid is at the same concentration inthe test and control solutions, and each solution is scored on a numericscale of 1 to 5, wherein 1 is the most bitter and 5 is the least bitter,for example, as performed in Example 1B. The taste test is performedwherein the solutions are at about the same temperature, or at aboutambient room temperature about 20 to 25° C. The solution is held in themouth for a period of at least 10 seconds during taste testing.

Flavoring Agent

In some embodiments, an aqueous formulation of tranexamic acid isprovided that is a solution formulation comprising a flavoring agent.Flavoring agents that can be added to the composition of the inventionare those known in the pharmaceutical art. Typically, the flavoringagent is selected from synthetic flavor oils and/or naturally derivedoils from plants, flowers, leaves, other natural flavors, natural fruitflavors, artificial flavors, artificial fruit flavors, or combinationsthereof. Naturally derived oils, other natural flavors, syntheticflavors or combinations thereof include, but are not limited to,peppermint, spearmint, menthol, cinnamon, vanilla, artificial vanilla,chocolate or artificial chocolate. Natural fruit flavors, artificialfruit flavors or combination thereof include, but are not limited to,cherry, grape, orange, strawberry or lemon. In some embodiments, theflavoring agent does not contain an aldehyde moiety. In one embodiment,the flavoring agent is menthol. In one embodiment, the flavoring agentdoes not include carvone. In some embodiments, the flavoring agent usedin the composition of the invention is present in a range of about 0.01to about 0.20%, or about 0.02 to about 0.10% wt/vol based on thecomposition.

Sweetener

In some embodiments, an aqueous solution formulation of tranexamic acidis provided that includes a sweetener. In some embodiments, thesweetener is an artificial or natural non-nutritive sweetener. In someembodiments, the sweetener is selected from aspartame (MethylL-α-aspartyl-L-phenylalaninate), acesulfame potassium (Potassium6-methyl-2,2-dioxo-2H-1,2λ⁶,3-oxathiazin-4-olate), neotame((3S)-3-(3,3-Dimethylbutylamino)-4-[[(2S)-1-methoxy-1-oxo-3-phenylpropan-2-yl]amino]-4-oxobutanoicacid), saccharin (2H-1λ⁶,2-Benzothiazol-1,1,3-trione), or sucralose((1→6)-Dichloro-(1→6)-dideoxy-β-D-fructofuranosyl-4-chloro-4-deoxy-α-D-galactopyranoside).In some embodiments, the sweetener is selected from the group consistingof xylose, ribose, glucose, mannose, galactose, fructose, dextrose,sucrose, maltose, sorbitol, xylitol, mannitol, pentaerythritol,stevioside, neohesperidin dihydrocalcone, thaumatin, glycyrrhizin,perillartine, cyclamate, and combinations thereof. In some embodiments,the sweetener is an artificial, i.e. non-sugar, sweetener. In a specificembodiment, the sweetener is sucralose. In some embodiments, thesweetener is used in the composition in a range of about 0.02 to 1wt/vol %, or 0.1 to 0.5 wt/vol % based on the weight of the compositionwhen an artificial sweetener is used.

Viscosity Enhancer

In some embodiments, an aqueous formulation of tranexamic acid isprovided that is a solution formulation comprising a pharmaceuticallyacceptable viscosity enhancer. The viscosity enhancer may be selectedfrom sorbitol, glycerin, ethylene glycol, propylene glycol, 1,3-butyleneglycol, polyethylene glycol, polypropylene glycol, xylitol, maltitol,lactitol, and mixtures thereof. In a specific embodiment, the viscosityenhancer includes propylene glycol. In some embodiments, the compositiondoes not include sorbitol. In some embodiments, the composition does notinclude glycerin. The viscosity enhancer in the composition of may rangefrom about 2 to about 8 wt %, or about 3 to about 6 wt %, or about 4 toabout 5 wt % of the composition.

Preservative

In some embodiments, an aqueous formulation of tranexamic acid isprovided that is a solution formulation comprising a preservative.Preservatives may be selected from any pharmaceutically acceptablepreservative known in the art. In some embodiments, the preservative isselected from sodium benzoate, potassium sorbate, EDTA or salts thereof,parabens (such as methyl, ethyl, propyl and butyl p-hydroxybenzoic acidsesters or mixtures thereof) or mixtures thereof. In some embodiments,methyl paraben, propyl paraben, sodium benzoate, or a mixture thereof isused as a preservative. In some embodiments, the preservative is presentin the aqueous tranexamic acid solution composition at from about 0.01to about 1.0 wt % based on the weight of the composition. In a specificembodiment, a mixture of methyl paraben and propyl paraben, is employedin a combined amount of from about 0.02 to about 0.5 wt %, or aboutabout 0.02 to 0.2 wt %, based on the weight of the composition. In someembodiments, the weight ratio of propyl paraben to methyl paraben isselected from about 1:2 to about 1:20, about 1:5 to about 1:15, or about1:9. In some embodiments, the presence of propyl paraben aids thelongevity of the preservative in the solution.

Administration

In one embodiment, a method is provided for treating a patient having ableeding disorder, or under fibrinolytic (thombolytic) agents and/or onanticoagulant therapy (e.g., warfarin) to reduce or prevent hemorrhageduring and/or following a dental procedure, comprising administering anaqueous pharmaceutical composition for topical administration in theoral cavity comprising tranexamic acid, according to the disclosure.

In some embodiments, the patient may suffer from a bleeding disorderselected from hemophilia A (factor VIII deficiency), hemophilia B(factor IX deficiency), von Willebrand disease, and other factordeficiencies including factor I, II, V, VII, X, XI, XII, or XIIIdeficiency.

In some embodiments, the patient may be on a fibrinolytic (thrombolytic)agent. In some embodiments, the fibrinolytic (thrombolytic) agent isstreptokinase, tissue plasminogen activator, or urokinase. In someembodiments, the fibrinolytic (thrombolytic) agent is a tissueplasminogen activator such as a human recombinant tissue plasminogenactivator (rtPA, e.g., Alteplase), derivative of recombinant human tPA(e.g., Retaplase), or Tenecteplase (TNK-tPA). In some embodiments, thefibrinolytic (thrombolytic) agent is a streptokinase (SK), such as anatural streptokinase, that has been isolated and purified fromstreptococci bacteria, or a complex of streptokinase and plasminogen(e.g., Anistreplase). In some embodiments, the fibrinolytic(thrombolytic) agent is urokinase (UK), a urinary-type plasminogenactivator (e.g, Abbokinase®). In some embodiments, the fibrinolyticagent is a New Oral Anticoagulant (NOAC) such as an oral direct thrombininhibitor (e.g. Dabigatran) or an oral direct factor Xa inhibitor (e.g.Rivaroxaban, Apixaban, or Edoxaban).

In some embodiments, the patient may be on anticoagulant therapy. Insome embodiments, the patient is on anticoagulant therapy selected fromWarfarin, Heparin, low molecular weight Heparin, Heparin sodium,Heparin/Dextrose, Dalteparin, Hirudin, Lepirudin, Bivalirudin,Argatroban, Dabigatran, Rivaroxaban, Apixaban, Edoxaban, Betrixaban,Darexaban, Letaxaban, Eribaxaban, Coumarin, Acenocoumarol,Phenprocoumon, Atromentin, Phenindione, Fondaparinux, or Idraparinux.

In some embodiments, a method is provided for treatment of a patientreceiving anticoagulant therapy during and following a dental procedureis provided comprising administering an oral aqueous mouth rinsesolution composition comprising an effective amount of tranexamic acid,as provided herein.

In some embodiments, a method is provided for treatment of a patienthaving a bleeding disorder, or patients on fibrinolytic (thrombolytic)therapy and/or receiving anticoagulant therapy, during and following adental procedure is provided comprising administering an oral aqueousmouth rinse solution composition comprising an effective amount oftranexamic acid, as provided herein.

In a specific embodiment, a method is provided for treatment of apatient in need thereof comprising administering a composition accordingto the disclosure topically in the oral cavity in a solution formcontaining 500 mg/10 ml (5 wt %) tranexamic acid. In some embodiments,the composition is administered topically in the oral cavity in the formof a solution as an oral rinse for two minutes, immediately after thedental procedure in a patient in need thereof, e.g., a patient withhemophilia, administration can be continued three or four times dailyfor up to eight (8) days.

A bleeding disorder is a condition that affects the way blood clots. Ableeding disorder prevents blood of a patient from clotting properly,which can result in prolonged or heavy bleeding. Bleeding disordersinclude hemophilia A and B that can occur when there are low levels ofclotting factors in the blood of the patient. It causes heavy or unusualbleeding into the joints. Factor II, V, VII, X or XII deficiencies arebleeding disorders related to blood clotting problems or abnormalbleeding problems. Von Willebrand's disease is the most common inheritedbleeding disorder. It develops when the blood of the patient lacks vonWillebrand factor, which helps the blood to clot. Certain bleedingdisorders, including hemophilia, can be treated by with factorreplacement therapy. Involving injection of clotting actorsintravenously to the patient. In some cases if the patient with ableeding disorder lacks certain clotting factors, a frozen plasmatransfusion may be employed. Fresh frozen plasma contains factors V andVIII, which help with clotting. The transfusion must be performed in ahospital.

A patient having a bleeding disorder is typically diagnosed by acomplete blood count (CBC) which measures the amount of red and whitecells, a platelet aggregation test, which checks how well platelets ofthe patient clump together, and a bleeding time test, which determineshow quickly the blood clots to prevent bleeding.

In some embodiments, the composition is indicated in patients withhemophilia or another bleeding disorder for short-term use for one totwelve days, one to ten days, two to eight days, or three to seven daysto reduce or prevent hemorrhage and/or to reduce the need for factorreplacement therapy during and following dental procedures. Thecomposition may be administered for a period of at least one, two,three, four, five, six, seven, eight, nine, ten, eleven or twelve daysto reduce or prevent hemorrhage and/or to reduce the need for factorreplacement therapy during and following dental procedures.

In some embodiments, a method is provided comprising administering anoral rinse dosage form as provided herein comprising tranexamic acid fortopical administration to the mouth of a patient in need thereof duringor after a dental procedure such as tooth extraction or scaling in orderto reduce bleeding, facilitate the use of antifibrinolytic therapy indental patients and/or minimize systemic exposure from administration ofthe injection dosage form.

In some embodiments, a method for treating a patient in need thereofcomprises administering the aqueous solution composition comprisingtranexamic acid according to the disclosure topically to significantlyreduce bleeding following dental procedures. In some embodiments, theoral mouth rinse composition according to the present disclosure isadministered topically as a mouth rinse in a swish and spit format in anamount in the range of 2 mL to 20 mL, 5 mL to 15 mL, or about 10 mL. Themouth rinse is swished and/or held in the mouth for a period of fromabout 30 seconds to about 4 minutes, about 1 min to about 3 min, orabout 2 minutes per administration. In some embodiments, the compositionis administered one, two, three, four, five, six, seven, eight, nine orten times per day for a period of one, two, three four, five, six,seven, eight, nine or ten days following the dental procedure. In aspecific embodiment, the mouth rinse is administered as an effectiveamount of 10 mL of a tranexamic acid 5% wt/vol solution used for twominutes, four times daily for seven days. In another specificembodiment, the mouth rinse is administered as an effective amount of 10mL of a tranexamic acid 5% wt/vol solution used for two minutes, fourtimes daily for five days. In one embodiment, the mouth rinse comprisingtranexamic acid is administered in a swish and spit format. In anotherembodiment, the mouth rinse comprising tranexamic acid is administeredin a swish and swallow format.

EXAMPLES Example 1A. Formulation Development

A Tranexamic Acid (TXA) Oral Rinse 5% formulation (Formulation A) wasdeveloped as shown in Table 1A. This formula was optimized in terms oftaste and preservative effectiveness using glycerin and sorbitol.However, it was found that it discolored (turned brownish) when placedon stability at 40° C./25% RH (relative humidity) within 1 month.

TABLE 1A Composition of Formulation A Component Functionality % (w/w)PURIFIED WATER USP Diluent 49.55 GLYCERIN, USP Viscosity enhancer 18.02PROPYLENE GLYCOL, Viscosity enhancer 1.8 USP SORBITOL 70%, USP Viscosityenhancer 18.02 TRANEXAMIC ACID Active 4.5045 (TXA) CONCENTRATED pHadjuster 0.288 PHOSPHORIC ACID, UN 1805 (Fisher) POLOXAMER 407Surfactant 0.36 (KOLLIPHOR ® P 407), 50259528 (BASF) SUCRALOSE Sweetener0.063 PURIFIED WATER USP Diluent 1.8 METHYLPARABEN, NF Preservative0.081 PROPYLPARABEN, NF Preservative 0.009 SPEARMINT FLAVOR, Flavoring0.36 (F-4785) Foote &Jenks PURIFIED WATER USP Diluent QS Total 100.0

To determine which components of the formulation were responsible forthe discoloration, binary mixtures of TXA and each component weredissolved in phosphoric acid solution at pH 5.5 in amountsrepresentative to their concentration in Formulation A of Table 1A.Binary mixtures are shown in Table 1B.

TABLE 1B Binary mixtures used to test for discoloration (wt %) SampleSample Sample Sample Sample Sample Sample INGREDIENT #1 #2 #3 #4 #5 #6#7 Glycerin, USP — — 20.0  — — — — Propylene Glycol, — — — 2.0 — — — USPSorbitol 70%, USP — — — 20.0  — — Tranexamic acid 5.0 5.0 5.0 5.0 5.05.0 5.0 Concentrated   0.28 *   0.28 *   0.28 *   0.28 *   0.28 *  0.28 * Phosphoric acid Poloxamer 407 — — — — —  0.80 — (KOLLIPHOR ® P407) Sucralose — — — — — —  0.10 Purified Water USP QS Total 100 100   100    100    100    100    100   

Samples of each mixture in Table 1B were placed in glass vials andstored in 60° C. oven for 2 weeks and visually inspected periodicallyfor discoloration. The samples from Table 1B containing TXA and Sorbitol(sample 5), or TXA and Glycerin (sample 3), or TXA and Poloxamer 407(sample 6), or TXA and spearmint flavor F-4785, turned yellow. Thussorbitol, glycerin, poloxamer 407 and spearmint flavor were consideredto be the ingredients responsible for the discoloration of formula A.

The approach to find alternatives to these components was focused onmaintaining the good taste of the formula with alternatives thatmaintain the properties/functions that Sorbitol, Glycerin, and Poloxamer407 exhibit in Formulation A of Table 1A. For example, Poloxamer 407 isa surfactant that helps dissolve the flavor. Sorbitol and Glycerin areconsidered as secondary sweeteners and viscosity enhancers in theformula that help with masking the bitter taste of TXA.

Alternative Flavoring to Spearmint Flavor F-4785

Natural extract flavors are composed of multi ingredients and maycontain aldehyde components which may react with the primary amine groupof the TXA resulting in discoloration. Searching for alternatives tonatural extract flavors was focused on finding a flavoring agent thatwas aldehyde-free, single component, and preferably natural. Mentholfulfilled all these requirements. It is a single ingredient, naturalessential oil that does not contain an aldehyde functional group in itsstructure and is widely used in consumer health and pharmaceuticalpreparation even though the flavor profile is less complex than anatural extract flavor like the spearmint oil. Menthol was selected forfurther evaluation.

Alternative Surfactants to Poloxamer 407

There are several surfactants that are commonly used in pharmaceuticalpreparations. To find alternatives to Poloxamer 407 which is commonlyused in mouthwash preparations, the following surfactants were tested:Tween 20, Tween 80, Sucrose Stearate, and Sucrose Laurate.

Binary Mixtures Study

Binary mixtures of TXA and alternative surfactants were prepared andsamples were stored in a 60° C. oven to test for discoloration asdescribed in Table 2.

TABLE 2 Binary mixtures of TXA and surfactants Tween 20, Tween 80,Sucrose Laurate, and Sucrose Stearate Amount (g) Sample Sample SampleSample INGREDIENT Item# Lot# #1 #2 #3 #4 Tranexamic 100132 R11845 5.05.0 5.0 5.0 acid Concentrated Fisher 154772 0.28 0.28 0.28 0.28Phosphoric UN acid 1805 Tween 20 Fisher 153083 0.5 — — — BP337- 500Tween 80 Fisher 151141 — 0.5 N/A — BP338- 501 Sucrose 420615- S00029 — —0.5 — Stearate S Sucrose 410413- S00030 — — — 0.5 Laurate S Purified200091 N/A QS QS QS QS Water USP Total 100 100 100 100 Discoloration NoNo Didn't No dissolve N/A = not applicable

1.2 Results

Tween 20, Tween 80 and Sucrose Laurate didn't cause discoloration whencombined with TXA and were considered as alternatives to Poloxamer 407.Sucrose Stearate did not dissolve into solution and was excluded fromfurther development. Initial testing was focused on Tween 80 because itis more commonly used in pharmaceutical preparations.

Alternatives to Glycerin and Sorbitol

Glycerin and Sorbitol were used in the initial formulation developmentas secondary sweeteners and to improve the mouth feel of the product byenhancing the viscosity of the preparation. They are widely used inpharmaceutical preparation and can be incorporated at very highconcentrations (up to 100%). There are many non-sugar sweetenersavailable, but they are similar to Sorbitol, and thus excluded fromconsideration.

Hydrophilic polymers such as cellulose based polymers were investigatedto increase viscosity in pharmaceutical preparation such as gels orpastes. Sodium carboxymethyl cellulose (Na CMC) is widely used in solidpharmaceutical and cosmetic preparations. Sodium carboxymethyl cellulosewas considered as a thickening agent to replace or augment Sorbitol andGlycerin, but it has no sweetening properties.

Binary Mixtures Study

Binary mixtures of Na CMC and TXA were prepared and stored at 60° C. for2 weeks to test for discoloration as in Table 3.

TABLE 3 Binary mixtures of TXA and CMC INGREDIENT Item# Lot# Amount (g)Tranexamic acid 100132 R11845 5.0 Concentrated Fisher UN 154772 0.28Phosphoric acid 1805 Sodium CMC 200206 R09629 0.5 Purified Water USP200091 N/A QS Total 100 Discoloration No

Results: Sodium CMC didn't cause discoloration. So it was considered asan alternative to Glycerin and Sorbitol for further development.

Tween 80 Based Formulations

Formulation development was next focused on using Tween 80, NaCMC, andMenthol at varying concentrations as described in Table 4A.

TABLE 4A Composition of formulations containing Tween 80, CMC andMenthol % (w/v) Formulation Formulation Formulation Component B C DPURIFIED WATER 80.0 80.0 80.0 USP PROPYLENE 5.0 5.0 7.0 GLYCOL, USPSODIUM CMC 1.0 0.75 0.5 TRANEXAMIC 5.0 5.0 5.0 ACID CONCENTRATED 0.3 0.30.3 PHOSPHORIC ACID SUCRALOSE 0.3 0.3 0.3 METHYLPARABEN, 0.18 0.18 0.18NF PROPYLPARABEN, 0.02 0.02 0.02 NF TWEEN 80 0.5 0.5 0.75 PURIFIED WATER5.0 5.0 5.0 USP MENTHOL 0.05 0.03 0.03 PURIFIED WATER QS QS QS USP Total100 1.0 L

Observations regarding taste and formulation characteristics forformulations B, C and D are shown in Table 4B.

TABLE 4B Observations regarding taste and formulation characteristicsfor formulations B, C and D Observations Formulation Changes EvaluationFormulation Control (baseline) Viscous (High NaCMC B Formulation:level), Burning sensation Propylene glycol = 5% from Menthol NaCMC = 1%Menthol = 0.05% Formulation Propylene glycol = 5% Tasted Better than CNaCMC = 0.75% Formulation B. No burning Menthol = 0.03% taste. Stillviscous. Turned cloudy when placed at 60° C. (Menthol was separatingout) within 1 day but went back into solution when cooled to RoomTemperature Formulation Propylene glycol = 7% Increased Tween 80 and DNaCMC = 0.5% Propylene glycol levels to Menthol = 0.03% prevent phaseseparation. Lowered CMC to reduce viscosity. Taste was good andViscosity was acceptable Turned cloudy when placed at 60° C. (Mentholwas separating out) within 1 day but went back into solution when cooledto Room Temperature

Alternatives to Tween 80 Based Formulations

Alternatives to Tween 80 formulations were focused on using Tween 20 andSucrose Laurate since they didn't cause discoloration when mixed withTXA and stored at 60° C. as described in Table 5A.

TABLE 5A Composition of formulations containing Tween 20 and SucroseLaurate % (w/v) Component Formulation E Formulation F PURIFIED WATER USP80.0 80.0 PROPYLENE GLYCOL, USP 5.0 5.0 SODIUM CMC 0.5 0.5 TRANEXAMICACID 5.0 5.0 CONCENTRATED 0.37 0.37 PHOSPHORIC ACID SUCRALOSE 0.3 0.3METHYLPARABEN, NF 0.18 0.18 PROPYLPARABEN, NF 0.02 0.02 TWEEN 20 — 0.5SUCROSE LAURATE 0.5 — PURIFIED WATER USP 5.0 5.0 MENTHOL 0.03 0.03PURIFIED WATER USP QS QS Total 100 100

Observations regarding taste and formulation characteristics forformulations E and F are shown in Table 5B.

TABLE 5B Observations regarding taste and formulation characteristicsfor formulations E and F Formulation Changes Evaluation FormulationSucrose Laurate = 0.5% Tasted good. E Propylene glycol = 5% Turnedcloudy when placed at NaCMC = 0.5% 60° C. (Menthol was Menthol = 0.03%separating out) within 1 day and didn't go back in solution when cooledto Room Temperature. Was eliminated from further development FormulationTween 20 = 0.5% Tasted good. F Propylene glycol = 5% Turned cloudy whenplaced at NaCMC = 0.5% 60° C. (Menthol was Menthol = 0.03% separatingout) after 2 weeks but back in solution when cooled to Room Temperature

Results: Formulation F tasted good but turned cloudy after 2 weeks at60° C. The sample went back into solution quickly when cooled down toroom temperature. This formulation was considered promising and was usedfor further development in attempts to prevent phase separation at 60°C. by increasing the concentration of Tween 20 from 0.5% to % and 1.0%.Additionally, Na CMC level was tested at 0.5% and at 0.25% to test itsimpact on taste and viscosity. Formulations are shown in Table 6.

TABLE 6 Composition of formulations containing Tween 20 and SucroseLaurate % (w/v) Component Formulation G Formulation H PURIFIED WATER USP80.0 80.0 PROPYLENE GLYCOL, 5.0 5.0 USP SODIUM 0.5 0.25 CARBOXYMETHYL-CELLULOSE TRANEXAMIC ACID 5.0 5.0 CONCENTRATED 0.37 0.34 PHOSPHORIC ACIDSUCRALOSE 0.3 0.3 METHYLPARABEN, 0.18 0.18 NF PROPYLPARABEN, NF 0.020.02 TWEEN 20 1.0 0.75 PURIFIED WATER USP 5.0 5.0 MENTHOL 0.03 0.03PURIFIED WATER USP QS QS Total 100 100

Results: Formulas with Tween 20 concentration at 0.75% and 1.0%prevented phase separation of Menthol at 60° C. Additionally lowering NaCMC level from 0.5 to 0.25% provided enough viscosity and maintained agood taste similar to formula F [[RD059-67(66?)]]. Formulations G and Hwere used for further development.

Refining Sodium Carboxymethyl Cellulose Levels and Taste Testing ofFormulations Example 1B. Taste Testing

A study was performed to determine the amount of sodium carboxymethylcellulose by preparing and testing new formulations containing of 0.5,0.25, 0.1 and 0% Na CMC for palatability scoring for taste andviscosity.

Four (4) test formulations of Tranexamic acid (TXA) 5% wt/vol oral rinsewere prepared as shown in Table 7 using Tween 20 surfactant with varyingamounts of Sodium carboxymethyl cellulose (Na CMC) of 0.5, 0.25, 0.1 and0%. The formulations were ranked in terms of taste and favorability incomparison to a control formulation containing TXA 5% wt/vol solution inwater.

Four formulations with varying amounts of Na CMC were prepared for tastetesting as described in Table 7.

TABLE 7 TXA 5 wt % Formulations for taste testing Formu- Formu- Formu-Formu- lation lation lation lation I J K L Component wt % wt % wt % wt %PURIFIED WATER 78.43 78.43 78.43 78.43 USP PROPYLENE 4.90 4.90 4.90 4.90GLYCOL, USP SODIUM CMC 0.49 0.245 0.098 0.0 TRANEXAMIC 4.90 4.90 4.904.90 ACID, FISHER UN1805 CONCENTRATED 0.363 0.33 0.33 0.33 PHOSPHORICACID SUCRALOSE 0.29 0.294 0.294 0.294 METHYLPARABEN, 0.18 0.176 0.1760.176 NF PROPYLPARABEN, 0.020 0.020 0.020 0.020 NF TWEEN 20, FISHER 0.980.735 0.735 0.735 BP337-500 PURIFIED WATER 4.90 4.90 4.90 4.90 USPMENTHOL, USP 0.029 0.029 0.029 0.029 PURIFIED WATER QS QS QS QS USPTotal 100.0 100.0 100.0 100.0

The taste testing was based on a swish and spit procedure. Each subjecttook approximately 3-5 mL of each formulation and swished the product inhis/her mouth for at least 10 seconds and spit the product into a wastecontainer. The subject rinsed his/her mouth with water to remove anyresidual amount of the product after each test. In addition to the fourtest formulations, a control formulation was employed consisting of 5%wt/vol TXA in water.

A panel of 8 tasters scored each of the four test formulations and thecontrol formulation. Each formula was evaluated for palatability scoreon a favorability scale from 1 (least favorable) to 5 (most favorable)for each of the following properties:

-   -   1. Level of sweetness    -   2. Level of flavor    -   3. Level of bitterness/after taste    -   4. Overall likability

At the end of test the formulas were ranked in terms of averagepalatability score by combining the individual scores of each formula.Taste test results are shown in Tables 8A to 8F.

TABLE 8A Taste Test -Control TXA Water Solution Control Level of Levelof Bitterness/ Overall TXA water sweetness flavor aftertaste likabilityK1 1 1 1 1 K2 1 2 1 1 K3 3 2 3 4 K4 1 1 3 2 MB 1 1 1 1 MA 1 1 1 1 ED 1 11 1 LSY 1 1 1 1 avg 1.25 1.25 1.5 1.5 Std Dev 0.71 0.46 0.93 1.07

TABLE 8B Taste Test -Formulation I Level of Level of Bitterness/ OverallForm I sweetness flavor aftertaste likability K1 3 4 5 4 K2 3 3 2 3 K3 42 1 1 K4 2 3 4 3 MB 2 3 3 3 MA 5 4 2 2 LSY 4 1 2 2 Avg 3.29 2.86 2.712.57 Std Dev 1.11 1.07 1.38 0.98

TABLE 8C Taste Test -Formulation J Level of Level of Bitterness/ OverallForm J sweetness flavor aftertaste likability K1 2 4 4 3 K2 2 3 3 3 K3 22 3 3 K4 3 4 4 4 MB 3 4 4 3 MA 4 3 3 3 LSY 3 2 3 3 ED 2 2 4 3 Avg 2.633.00 3.50 3.13 Std Dev 0.74 0.93 0.53 0.35

TABLE 8D Taste Test -Formulation K Level of Level of Bitterness/ OverallForm K sweetness flavor aftertaste likability K1 1 1 2 2 K2 2 3 3 3 K3 22 3 2 K4 3 2 3 3 MB 2 3 2 2 MA 5 4 4 4 LSY 4 4 5 5 ED 2 3 3 3 Avg 2.632.75 3.13 3.00 STDEV 1.30 1.04 0.99 1.07

TABLE 8E Taste Test -Formulation L Level of Level of Bitterness/ OverallForm L sweetness flavor aftertaste likability K1 1 1 2 1 K2 1 1 2 2 K3 21 2 1 K4 3 3 3 3 MB 2 2 2 2 MA 5 3 4 4 LSY 3 3 4 4 ED 2 2 3 3 AVG 2.382.00 2.75 2.50 STDEV 1.30 0.93 0.89 1.20

The test formulations were each substantially less bitter that thecontrol formulation containing tranexamic acid and water. Specifically,each of Formulations I, J, K, and L comprising 5% wt/vol tranexamic acidexhibited average bitterness score of 2.71(±1.38), 3.50(±0.53),3.13(±0.99), and 2.75 (±0.89), respectively, whereas the controlcontaining tranexamic acid 5 wt/vol % in water exhibited averagebitterness scale of 1.50 (±0.93), according to the 5 point relativebitterness scale provided herein. In some embodiments, aqueoustranexamic acid compositions are provided comprising no less than 40%water by volume, a thickener and a surfactant that exhibit less averagebitterness than a control solution consisting of tranexamic acid inwater and score at least 1.0 average points higher, or at least 1.5average points higher on a 5 point bitterness scale wherein 1 is mostbitter and 5 is least bitter.

The individual scores for sweetness, flavor, bitterness/aftertaste andoverall likability were added and averaged to arrive at overall resultsof the taste test which are shown in Table 8F. The formula with highestoverall score was selected as the lead formula.

TABLE 8F Overall Taste Testing Results Formula # Control (5% Formu-Formu- Formu- Formu- wt/vol TXA lation lation lation lation Subject #water solution) I J K L K1 4 16 13 6 5 K2 5 11 11 11 6 K3 12 8 10 9 6 K47 12 15 11 12 MB 4 11 14 9 8 ED 4 15 11 11 10 MA 4 13 13 17 16 LSY 4 911 18 14 AVG 5.5 11.9 12.3 11.5 9.6 STDEV 2.8 2.7 1.8 4.1 4.1 # ofhighest 1 3 3 3 0 score

Formulations I, J, K and L exhibited average palatability scores of 11.9(±2.7), 12.3 (±1.8), 11.5 (±4.1), and 9.6 (±4.1), respectively. Incontrast, control formulation consisting of 5% wt/vol TXA in waterexhibited average palatability score of 5.5 (±2.8). Formulation J thatcontains Tween 20 at ˜0.75% (w/v) and Sodium CMC 0.25% (w/v) receivedthe highest overall average score for palatability based on sweetness,flavor, level of bitterness/aftertaste, and overall likability, as wellas the lowest variability. Formulations I and J were selected forstability studies.

Example 2A. Stability Studies

Batches of Formulations I and J were prepared according to Table 8G andsubjected to stability studies.

TABLE 8G Formulations I and J for Stability Studies Formulation IFormulation J % Theoretical % Theoretical Component w/w Quantity (g) w/wQuantity (g) Purified Water USP 78.43 800.0 78.43 800.0 PropyleneGlycol, USP 4.90 50.0 4.90 50.0 Sodium 0.49 5.0 0.25 2.5Carboxymethylcellulose Tranexamic acid 4.90 50.0 4.90 50.0 ConcentratedPhosphoric 0.36 3.7 0.33 3.4 acid Sucralose 0.29 3.0 0.29 3.0Methylparaben, NF 0.18 1.8 0.18 1.8 Propylparaben, NF 0.02 0.2 0.02 0.2Tween 20 0.98 10.0 0.74 7.5 Purified Water USP 4.90 50.0 4.90 50.0Menthol, USP 0.029 0.3 0.029 0.3 Purified Water USP QS QS QS QS Total100 1020.0 g 100 1020.0 g

Formulations I and J were stored in HDPE bottles at 25° C. at 40%relative humidity (RH), and at 40° C./25% RH, as well as freeze/thawconditions. Samples were assayed by Liquid chromatography was performedat baseline, and at each time point for tranexamic acid, propyl parabenand methyl paraben. pH of the formulations was monitored at each timepoint. Discoloration was also monitored.

Stability data under accelerated stability conditions when stored at 40°C./25% RH conditions is shown in Tables 9 and 10 below for FormulationsI and J, respectively.

TABLE 9 12 Month Stability data: Formulation I at 40° C./25% RH HDPEbottles TXA Pr. Me. Sample assay Paraben Paraben Degradants Colordescription (% LC) (% LC) (% LC) (% LC) 1* a* b* ΔΕ pH Initial 101.199.9 98.6 <RPT 99.77 −0.24 1.19 n/a 5.5 1 Month 100.5 98.0 94.6 UU0325 =99.68 −0.42 2.07 0.90 5.5 0.53 Total = 0.53 2 Months 100.2 95.4 97.8UU0325 = 1.1 99.7 −0.49 2.41 1.25 5.5 UU0434 = 0.2 Total = 1.3 3 Months101.1 96.5 94.6 <RPT ¹ 99.51 −0.67 3.09 1.97 5.5 6 Months 100.7 98.998.8 RC-C < RPT 99.39 −0.82 4.09 2.98 5.5 RC-D < RPT UU0324 = 0.08 Total= 0.08 12 Months Freeze- 101.7 98.5 95.2 UU0325 = 0.1 99.94 −0.26 1.330.22 5.5 Thaw Total = 0.1 ¹ Previously reported Degradant at UU0325 wasfound to be related to placebo so it was dropped from calculation and nolonger tracked after 2 month data point. “UU” refers to UnspecifiedUnidentified. “<RPT” refers to below reporting threshold.

TABLE 10 12 Month Stability data: Formulation J at 40° C./25% RH HDPEbottles TXA Pr. Me. Sample assay Paraben Paraben ¹Degradants Colordescription (% LC) (% LC) (% LC) (% LC) 1* a* b* ΔΕ pH Initial 100.698.5 98.1 <RPT 99.86 −0.19 0.81 n/a 1 Month 100.3 96.55 94.05 UU0325 =0.59 99.81 −0.17 1.14 0.33 5.5 Total = 0.59 2 Months 100.5 95.65 96.95UU0325 = 1.2 99.81 −0.23 1.43 0.62 5.5 UU0434 = 0.2 Total = 1.4 3 Months100.6 95.3 94.35 <RPT ¹ 99.63 −0.38 1.99 0.82 5.5 6 Months 100.4 97.298.3 RC-C < RPT 99.63 −0.47 2.57 1.79 5.5 RC-D < RPT UU0324 = 0.09 Total= 0.09 12 Months Freeze-Thaw 100.3 96.2 94 UU0325 = 0.12 99.84 −0.070.75 0.14 5.5 Total = 0.12 ¹Previously reported Degradant at UU0325 wasfound to be related to placebo so it was dropped from calculation after2 month time point. “UU” refers to Unspecified Unidentified.. “<RPT”refers to below reporting threshold.

Results: The compositions of both Formulation I and Formulation J werecapable of maintaining at least about 99.0%, 99.5%, or 99.9% of therelease, or “as manufactured,” amount of tranexamic acid in undegradedform after storage for 6 months at 40° C. at 25% relative humidity, asshown in Tables 9 and 10.

The compositions of both Formulation I and Formulation J were capable ofmaintaining at least about 95% of the release, or “as manufactured,”amount of propyl paraben in undegraded form after storage for 6 monthsat 40° C. at 25% relative humidity.

The compositions of both Formulation I and Formulation J were capable ofmaintaining at least about 93% of the release, or “as manufactured,”amount of methyl paraben in undegraded form after storage for 6 monthsat 40° C. at 25% relative humidity.

The composition of Formulations I and J did not exhibit significantdiscoloration after storage for 6 months at 40° C. at 25% relativehumidity and exhibited ΔE*<5.

The compositions of both Formulation I and Formulation J were capable ofmaintaining pH 5.5 after storage for 6 months at 40° C. at 25% relativehumidity.

Stability data for first six months for the 25° C./40% RH conditions isshown in Tables 11 and 12 below for Formulations I and J, respectively.

TABLE 11 12 Month Stability data: Formulation I at 25° C./40% RH HDPEbottles TXA Pr. Me. Sample assay Paraben Paraben Degradants Colordescription (% LC) (% LC) (% LC) (% LC) 1* a* b* ΔΕ pH Initial 101.199.9 98.6 <RPT ¹ 99.77 −0.24 1.19 n/a 5.5 3 Months 100.6 96.7 94.2 <RPT99.61 −0.42 2.01 0.85 5.5 6 Months 100.6 100.5 100.4 RC-C <RPT 99.71−0.39 1.93 0.8 5.5 RC-D < RPT Total < RPT 12 Months Freeze-Thaw 101.798.5 95.2 <RPT 99.94 −0.26 1.33 0.2 5.5 ¹ “<RPT” refers to belowreporting threshold.

TABLE 12 12 Month Stability data: Formulation J at 25° C./40% RH HDPEbottles TXA Pr. Me. Sample assay Paraben Paraben ¹Degradants Colordescription (% LC) (% LC) (% LC) (% LC) 1* a* b* ΔΕ pH Initial 100.698.5 98.1 <RPT ¹ 99.86 −0.19 0.81 n/a 5.5 3 Months 100.4 95.1 93.6 <RPT99.63 −0.38 1.99 0.82 5.5 6 Months 100.6 99.1 100.1 RC-C < RPT 99.79−0.17 1.16 0.4 5.5 RC-D < RPT Total < RPT 12 Months Freeze-Thaw 100.396.2 94 <RPT 99.84 −0.07 0.75 0.1 5.5 ¹“<RPT” refers to below reportingthreshold.

Results: The compositions of both Formulation I and Formulation J werecapable of maintaining at least about 99.0%, or at least about 99.5% ofthe release, or “as manufactured,” amount of tranexamic acid inundegraded form after storage for 6 months at 25° C. and 40% relativehumidity, as shown in Tables 11 and 12.

The compositions of both Formulation I and Formulation J were capable ofmaintaining at least about 95% of the release, or “as manufactured,”amount of propyl paraben in undegraded form after storage for 6 monthsat 25° C. at 40% relative humidity.

The compositions of both Formulation I and Formulation J were capable ofmaintaining at least about 93% of the release, or “as manufactured,”amount of methyl paraben in undegraded form after storage for 6 monthsat 25° C. at 40% relative humidity.

The compositions of both Formulation I and Formulation J did not exhibitsignificant discoloration after storage for 6 months at 25° C. at 40%relative humidity and exhibited ΔE*<5.

The compositions of both Formulation I and Formulation J were capable ofmaintaining pH 5.5 after storage for 6 months at 25° C. at 40% relativehumidity.

Example 2B. HPLC Methods for Quantitation of the Active, Preservativesand Degradants in Tranexamic Acid Oral Rinse, 5% w/v

The following HPLC method was employed for analysis of Tranexamic acidoral rinse formulations. Target analytes include active pharmaceuticalingredient tranexamic acid (TXA), preservative methylparaben (MPB), andpreservative propylparaben (PPB). Drug product labeled amounts fortranexamic acid (TXA) were 5% w/v or 50 mg/mL; methylparaben (MPB) 1.8mg/mL; and propylparaben (PPB) 0.2 mg/mL.

An HPLC with UV detector was fitted with C16 reverse phase column(Dionex Acclaim Polar Advantage (PA) C16, 5 um, 4.6×250 mm). Flow ratewas 1.0 mL/min at 25° C. column temperature. An injection volume of 15uL was employed. Eluate was monitored at 220 nm.

Mobile phase A was prepared by dissolving 1.2 g basic ammonium phosphateand 3.66 g of sodium perchlorate in 1000 mL deionized water (18 megaohmwater). Mobile phase B was acetonitrile. HPLC gradient elution was runaccording to Table 13A.

TABLE 13A HPLC Gradient Profile Time (minutes) % Mobile Phase A % MobilePhase B 0.00 97 3 7.00 97 3 35.00 40 60 36.00 97 3 42.00 98 3

Stock and working standard solutions of MPB/PPB and TXA were prepared.Reporting threshold standard preparation was 0.005 mg/mL TXA.

Retention time (RT), Relative retention time (RRT) relative to TXA, andRelative response factors (RRF) for TXA, MPB, PPB and related compoundsA, B, C, and D are shown in Table 13B.

TABLE 13B HPLC Retention Times, Relative Retentions times compared toTXA, and Response Factors for analytes RRT (Relative to Analyte RT(min)TXA) RRF TXA 7.07 1.00 NA USP Related 7.84 1.11 0.006 Compound C (RC C)USP Related 8.89 1.26 0.84 Compound B (RC B) USP Related 9.62 1.36 0.006Compound D (RC D) USP Related 20.78 2.94 1.23 Compound A (RC A) MPB25.68 3.63 NA PPB 32.71 4.63 NA

The chemical structures of tranexamic acid and degradant compounds A, B,C and D are shown in FIG. 1 .

Tranexamic acid related compound A:trans-trans-4,4′-Iminodimethylenedi(cyclohexanecarboxylic acid) is alsoknown as “tranexamic acid dimer”

Tranexamic acid related compound B:cis-4-(aminomethyl)cyclohexanecarboxylic acid is also known as“cis-tranexamic acid”.

Tranexamic acid related compound C:((RS)-4-aminomethyl)cyclohex-1-enecarboxylic acid is also known as“1,2-didehydro tranexamic acid”.

Tranexamic acid related compound D is 4-Aminomethylbenzoic acid. Systemssuitability is maintained when performing sample analysis.

The amount of each of TXA, MPB, PPB in the sample compared to standardsis calculated and reported to one decimal place. The amount of TXAdegradants in the sample compared to standards is calculated andreported to one decimal place.

Example 2C. Method for Determination of Color (CLR) in Drug Product,Tranexamic Acid Oral Solution (TXA OS), 5% w/v

A key factor in maintaining the quality of a pharmaceutical product isthe color of the drug product in its final form. A colorimetric assay isused to determine the consistency of the color of drug product frombatch to batch as well as throughout it shelf life by measuring changesin the product's color over time.

In this test method, the color analysis of the drug product isdetermined from at least one randomly chosen sample. A ColorimetricSpectrophotometer (e.g., HunterLab or equivalent may be employed. Theinstrument software (e.g. EasyMatchQC® software) is configured to readusing the desired color scale, illuminant, and observer. Thetransmission cell holder is installed and the instrument is standardizedas described in User's Manual. The TTRAN mode or TTRAN mode and largearea view (LAV) port plate and lens position is used.

Sample is added to fill sample cell and centered over transmission port.A single color reading of the sample is taken, sample is removed, thenreplaced into compartment and color is read once more. The multiplecolor readings for a single color measurement are averaged. The averageCLR values are recorded using color scale L*, a*, b* as a full colordescriptor. The CLR average L, a, b values are reported.

The Color is represented by the L*a*b* value where L* represents thelightness or darkness of the sample; a* represents the redness orgreenness of the sample; and, b* represents the yellowness or bluenessof the sample; ΔE* (delta E*) indicates the degree of color differenceand can be expressed as the root sum square of the differences in L*, ina*, and in b* from the initial L*, a*, and b* values (or the Euclideandistance).

Deltas for L* (ΔL*), a* (Δa*) and b* (Δb*) may be positive (+) ornegative (−). The total difference Delta E (ΔE*), however, is alwayspositive.

ΔL* (L* sample minus L* standard)=difference in lightness and darkness(+=lighter, −=darker);

Δa* (a* sample minus a* standard)=difference in red and green (+=redder,−=greener);

Δb* (b* sample minus b* standard)=difference in yellow and blue(+=yellower, −=bluer); and

ΔE*=total color difference.

To determine the total color difference in a colorimetric assay betweenall three coordinates, the following formula may be used:

ΔE*=[ΔL*2+Δa*2+Δb*2]½.

A delta E* (ΔE*) value of about 2.35 is defined as a color result thatis a Just Noticeable Difference (JND); with values less than (<) nochange is observable (not significant). The value of 2.35 is perceivedas the value at which the human eye can start detecting differences incolor. In some embodiments, tranexamic acid formulations are providedthat exhibit minimal discoloration as determined by ΔE*<3, <4, or <5after storage for at least 6 months at about 25° C. and about 40%relative humidity in a colorimetric assay.

A ΔE* value specification threshold in the range of <4, <5, <6, <7, <8,<9 or <10 may be employed to determine sample stability over time.

In a particular aspect, stable tranexamic acid compositions areprovided, exhibiting a ΔE* value of <5 when stored at 25° C. at 40% RHafter a period of 3 months, 6 months, 9 months, or 12 months. In anotherparticular aspect, stable tranexamic acid compositions are provided,exhibiting a ΔE* value of <5 when stored at 40° C. at 25% RH after aperiod of 3 months, 6 months, 9 months, or 12 months.

Clinical Studies

The following clinical studies will be performed to demonstrate thesafety and efficacy of Tranexamic Acid Mouth Rinse solution inpreventing bleeding in hemophilia patients following dental scalingprocedure. The intended indication of the Tranexamic acid oral rinsesolution is to treat patients with hemophilia for short-term use (two toeight days) to prevent or reduce hemorrhage, and reduce the need forreplacement therapy, during and following dental procedure.

Example 3.Tranexamic Acid Oral Rinse—Phase 1 Pharmacokinetic Study

An open label, randomized, two-treatment, single-dose and multiple-dosestudy will be performed to assess the pharmacokinetic and safety profileof Tranexamic Acid oral Rinse in maximal use and normal use conditionsin healthy subjects following tooth extraction.

The pharmacokinetic study will be performed with the objective to assessthe pharmacokinetic profile (Cmax, AUC0-t, AUC0-∞, Tmax, t½ and Kel) inmaximal use condition (swish and swallow) and normal use condition(swish and spit). This study will be conducted in healthy subjects whoare following a tooth extraction procedure to assess the effect of theoral wounds on the pharmacokinetic profile of Tranexamic acid oral rinsein plasma.

The primary objective of the study is (1) to characterize the absorptionof Tranexamic Acid oral rinse after administration of a single-dose inmaximal use condition (swish and swallow) and normal use condition(swish and spit), and (2) to characterize the pharmacokinetics oftranexamic acid after administration of a multiple-dose in maximal usecondition (swish and swallow) in healthy subjects following a toothextraction procedure. Time to clot formation will also be measured. Thesecondary objective of the study is to assess the safety andtolerability of Tranexamic acid oral rinse.

This is an open label, randomized, two-treatment, single dose study. Thedose of 10 mL of 5% Tranexamic Oral Rinse (500 mg/10mL) is selected forthe study as the administration by mouth rinsing of this dose leads to asaliva tranexamic acid level range (from 2.54 to 1.27 10³ μmol/L)corresponding to the in-vitro fibrinolysis inhibition activity levels ofthis compound (from 3.00 to 1.00 10³ μmol/L). This dose will also beused in the phase 3 study.

The subject will remain in the clinic at least 1 hour prior to studydrug administration and until 12 hours after study drug administration.

For Arm 1 and Arm 2, blood and saliva samples will be collected from allthe subjects in the study at pre-dose (0.00) and post-dose at 0.083,0.25, 0.50, 1.00, 1.50, 2.00, 2.50,

3.00, 3.50, 4.00, 8.00, 12.00 and 24.00 hours The subject will have tocome back to the clinical for the last blood sample draw, at 24 hourspost-administration. For Arm 3, blood and saliva samples will becollected from all the subjects in the study at pre-dose (0.00) andpost-dose at 1.00, 2.00, 3.00, 4.00, 5.00, 6.00, 7.00, 8.00, 8.50, 9.00,9.50, 10.00, 11.00, 12.00 and 24.00 hours.

A cannulation will be carried out before the pre-dose sample collectionand will be kept till the 12 hour sample collection. Later on, thecannula will be removed and sample collection will be done by directvenipuncture for the 24 hours sample collection. A medical examinationwill be performed at 24±2 hours post-dose.

36 healthy subjects (12 subjects per treatment arm) between 18 and 45years of age will be enrolled in the study. Inclusion criteria for eachsubject include healthy, human volunteer of age between 18 and 45 yearsold with a Body Mass Index (BMI) between 18.50 kg/m2 and 30.00 kg/m2(inclusive), and a body weight between 50 and 100 kg. Subjects scheduledto undergo tooth extraction (pre-molar, or molar, right or left, upperor lower).

Generally healthy as documented by the medical history, physicalexamination and vital sign assessments, non-smokers. If a female, mustbe postmenopausal (no spontaneous menses for at least 2 years),surgically sterile, abstinent, or, if sexually active, be practicing aneffective method of birth control before entry and throughout the study.If a female, must have a negative pregnancy test (plasma β-hCG) atScreening and Baseline.

Exclusion criteria include Subjects with congenital or acquiredconditions that predispose to bleeding (e.g. hemophilia,thrombocytopenia, coagulopathy, hematologic disease and moderate tosevere hepatic impairment) are excluded.

Treatment groups include:

-   -   Arm 1: Tranexamic Acid oral 10 mL of 5% wt/vol (500 mg/10 mL),        rinse swish and swallow (maximal use condition).    -   Arm 2: Tranexamic Acid oral 10 mL of 5% wt/vol (500 mg/10 mL),        rinse swish and spit (normal use condition)    -   Arm 3: Tranexamic Acid oral 10 mL of 5% wt/vol (500 mg/10 mL),        rinse swish and swallow (multiple dose maximal use condition)

For Arm 1 and Aim 2, the subject will remain in the clinical at least 1hours prior to study drug administration and until 12 hours after studydrug administration. The subject will come back to the phase 1 unit fora 24-hour post-dose visit. For Arm 3, the subject will be housed inclinic for not less than 12.00 hours prior to drug administration andtill 36.00 hours after drug administration. Check-out will be done onDay 2 of the study.

Safety assessments will include Adverse events, laboratory examination,Physical examination, ECG examination, vital signs.

Pharmacokinetic Parameters will include Cmax, AUC0-t, AUC0-∞, Tmax, t½,Kel and will be estimated for plasmatic Tranexamic Acid.

Overview of Statistical Plan Non-compartmental Analysis: for each PKparameters, except Tmax, the following summary statistics will becalculated: median, maximum, minimum, arithmetic mean with 95%confidence interval, SD, coefficient of variation, geometric mean with95% confidence interval and standard deviation of logarithmicallytransformed data. For Tmax, median, minimum, arithmetic mean and SD willbe calculated.

Example 4. Phase 3 Efficacy Study

A well-controlled study will be performed to demonstrate the efficacy ofTranexamic Acid Mouth Rinse solution is preventing bleeding inhemophilia patients following a dental scaling planning procedure.

This study will be a randomized, double-blind, controlled studycomparing the efficacy and safety of tranexamic acid as a mouth rinse tofactor replacement therapy in the prevention of bleeding followingdental procedure in patients with hemophilia.

The main objective of this study is to demonstrate that oral rinsesolution provided herein containing tranexamic acid is at least aseffective as factor replacement therapy (non-inferiority study) in thetreatment and prevention of bleeding following a dental procedure (rootscaling, teeth extraction and root canal) in patients with hemophilia.

The use of Tranexamic Acid Oral Rinse will reduce the need forreplacement therapy. Replacement Therapy are responsible for thedevelopment of inhibitors (Gringer, 2003), which may lead tolife-threatening conditions for the patients. A study from CDC (Walsh,2015) demonstrated that patients who had developed Replacement Therapyinhibitors are at 70% higher risk of mortality compared to those withoutinhibitors. Therefore, Tranexamic Acid Oral Rinse may have a clinicallymeaningful effect on prevention of a disease with potentially seriousoutcome, irreversible morbidity, or even mortality.

Previous clinical studies have demonstrated that the use of localantifibrinolytic therapy with Tranexamic acid as a supplement to thecurrently used systemic therapy significantly reduces in the incidencesof postoperative bleeding (Franchini, 2005), (Hamid, 2008), (Tavenner,1972) and (Forbes, 1972)).

In addition, A. H. P. Lee et al. in 2005 (Lee, 2005) and SivakumarNuvvula et al. in 2014 (Nuvvula, 2014), demonstrated the efficacy effectof Tranexamic Acid mouthwash in controlling bleeding after dentalscaling in people with hemophilia. They demonstrated that TranexamicAcid oral rinse formulation can be used as a supplement to FactorReplacement Therapy in dental scaling procedure. A 5% Tranexamic Acidaqueous solution (500 mg/10 mL) was used in these two clinical trials.

An oral rinse solution (Tranexamic acid oral rinse) according to thedisclosure will be used to treat patients with moderate and severehemophilia for short-term use (two to eight days) to prevent or reducehemorrhage, and reduce the need for replacement therapy, during andfollowing dental procedure.

The primary objective is to determine the effect of Tranexamic Acid oralrinse and FRT in bleeding events from Day 0 (post-procedure) to Day 7 inall patients.

The secondary objectives are to determine the effect of Tranexamic Acidoral rinse and FRT in the immediate post-procedure bleeding severity; todetermine the effect of Tranexamic Acid oral rinse and FRT (factorreplacement therapy) in the use of “on-demand” FRT when bleeds occurfrom Day 0 (post-procedure) to Day 7 in all patients; to time bleedingpost-procedure; and to assess the tolerability and safety of TranexamicAcid oral rinse and FRT.

This is a randomized, double-blind, active-controlled study.

The dose of 10 mL of 5% Tranexamic Oral Rinse (500 mg/10 mL) is selectedfor the study.

The patients will be randomized in a 1:1 ratio to the experimentaltreatment group involving saline transfusion followed by Tranexamic AcidOral Rinse, or the control treatment group involving FRT followed byvehicle mouthwash.

The patients will be asked to rinse their mouth with Tranexamic acid 5%aqueous solution (500 mg/10 mL) for 2-minute immediately followingdental procedure (root scaling, teeth extraction and root canal)planning, and for 2-minute 4 times daily during 7 days following dentalprocedure. The mouthwash solution must be swilled gently for 2-3 minutesand expelled.

The patient will remain 8 days on the trial, from dental procedure (Day0) to End-of-Study Visit (Day 7). The total duration of the treatment is8 days.

The last visit will happen at the End-of-Study Visit (Day 7) 7-dayspost-procedure.

Around 108 haemophilic patients scheduling to undergo a dental procedure(54 patients per arm) will be enrolled in the study.

Treatment groups include

-   -   Arm 1: placebo (matching to FRT injection)+Tranexamic acid−5%        Oral Rinse (500 mg/10 mL), one 2-minute oral rinse following        dental procedure, and one 2-minute oral rinse 4 times daily        during 7 days following dental procedure. The mouthwash solution        must be swilled gently for 2-3 minutes and expelled.    -   Arm 2: FRT injection, pre-operatively+vehicle (matching to TXA        oral rinse)

“On-demand” FRT is allowed during the course of the study (from Day 0 toDay 7) when bleeds occur (recorded by the patient in a diary card).

Efficacy assessments include for the primary objective to determine theeffect of Tranexamic Acid oral rinse and FRT in bleeding timepost-dental procedure.

Plasmin level in saliva and plasma before and after Tranexamic Acid OralRinse will be measured.

To determine the effect of Tranexamic Acid oral rinse and FRT on theimmediate post-dental procedure bleeding severity, bleedingclassification performed by the physician will use the following scale:

-   -   0—No bleeding    -   1—Light bleeding blood in saliva    -   2—Moderate Bleeding    -   3—Bleeding controlled with local measures    -   4—Severe Bleeding when surgical intervention is required

The number of bleeding events and bleeding score will be recorded,bleeding score will be recorded by the patient in a diary card from Day0 (post-procedure) to Day 7.

Bleeding score≤1 will be considered as minor bleeding events.

The bleeding classification will be performed by the patients using thefollowing scale:

-   -   0—No bleeding    -   1—Blood stained saliva    -   2—Bleeding that stopped after compression bandage and ice pack        for 20 minutes    -   3—Bleeding stopped only after professional intervention

We claim:
 1. A method for reducing or preventing hemorrhage in apatient's oral cavity during or following a dental procedure,comprising: topically administering in the oral cavity to a patient inneed of such treatment a therapeutically effective amount of an aqueouspharmaceutical solution comprising: about 3% wt/vol to about 7% wt/voltranexamic acid; greater than 50 wt % water; wt % to 1 wt %polyoxyethylene sorbitan monolaurate; wt % to 0.5 wt % sodiumcarboxymethyl cellulose; about 3 wt % to about 6 wt % propylene glycol;about 0.01 wt % to about 0.2 wt % menthol; about 0.02 wt % to about 0.5wt % of a mixture of propyl paraben and methyl paraben; and a pHadjuster in an amount sufficient to adjust the pH to 4.5 to 6.5; wherein(a) the solution does not include carvone or a flavoring agentcontaining an aldehyde moiety, (b) the solution retains at least about90% of the tranexamic acid in solution in undegraded form after storagefor 6 months at about 25° C. and about 40% relative humidity; and (c)the solution exhibits minimal discoloration as determined by deltaE*<5after storage for 6 months at about 25° C. and about 40% relativehumidity.
 2. The method of claim 1, wherein the patient has a bleedingdisorder, is under fibrinolytic or thrombolytic agent therapy, and/or ison anticoagulant therapy.
 3. The method of claim 2, wherein the patientis suffering from a bleeding disorder selected from hemophilia A,hemophilia B, von Willebrand disease or a factor deficiency.
 4. Themethod of claim 2, wherein the patient is taking a fibrinolytic orthrombolytic agent selected from streptokinase, tissue plasminogenactivator or urokinase.
 5. The method of claim 1, wherein the solutionis administered topically as a mouth rinse in a swish and spit format inan amount of 2 mL to 20 mL for about 30 seconds to 4 minutes peradministration.
 6. The method of claim 5, wherein the solution isadministered three to six times per day for a period of one to 10 days.7. The method of claim 6, wherein tranexamic acid is present in thesolution in an amount of 5% wt/vol, and about 10 mL of the compositionis administered 4-5 times daily for a period of 7 days.
 8. The method ofclaim 1, wherein the solution is administered during and/or following adental procedure, such as tooth extraction or scaling.
 9. The method ofclaim 1, wherein the solution exhibits an average palatability score ofat least two points higher than a control solution consisting oftranexamic acid and water.
 10. The method of claim 9, wherein thesolution exhibits an average palatability score of at least three pointshigher than a control solution consisting of tranexamic acid and water.11. The method of claim 1, wherein the solution exhibits lower averagebitterness than a control solution consisting of tranexamic acid andwater and scores at least 1.0 average points higher on a 5 pointbitterness scale wherein 1 is most bitter and 5 is least bitter.
 12. Themethod of claim 1, wherein the pH adjuster is phosphoric acid.
 13. Themethod of claim 12, wherein the phosphoric acid is present in an amountto adjust the pH of the solution to about 5.5.
 14. The method of claim1, wherein the pH adjuster is present in an amount to adjust the pH ofthe solution to about 5.5.
 15. The method of claim 1, wherein thesolution comprises from about 4% wt/vol to about 6% wt/vol tranexamicacid.
 16. The method of claim 1, wherein the solution comprises fromabout 5% wt/vol tranexamic acid.
 17. The method of claim 1, wherein thesolution comprises from about 30 mg/ml to about 70 mg/ml tranexamicacid.
 18. The method of claim 1, wherein the solution comprises fromabout 40 mg/ml to about 60 mg/ml tranexamic acid.
 19. The method ofclaim 1, wherein the solution comprises from about 50 mg/ml tranexamicacid.